Improvement in furnaces for steam-boilers



- 2Sheets-Sheet1 C. D. SM [T H.

Improvement in Furnaces for Steam-Boilers;

N0.1 30,249. Patented Aug. 6,1872.

Q Sheets Sheet 2. C. D. SMIT H.

Improvement in Furnaces for Steam-Boilers.

No, 130,249, Patented Aug. 6,1872.

fiz widow Wifnesses:

A. Q 3M U NITED STATES PATENT OEEIoE.

CHARLES D. SMITH, OF CHICAGO, ILLINOIS.

IMPROVEMENT IN FURNACES FOR STEAM-BOILERS.

Specification forming part of Letters Patent No. 130,249, dated August6, 1872.

Specification describing certain Improvements in Furnaces forSteam-Boilers, invented by CHARLES D. SMITH, of Chicago, Illinois.

My invention relates to the construction of furnaces for steam-boilers,which affords a perfect combustion of fuel, smoke, and gases with theaid of atmospheric air introduced, by means of extra channels, towardthe fire-surface of the boiler, and by means of superheated steamintroduced into the fire-box or furnace above the grates.

Figure 1 represents a side elevation of my improved furnace with boiler.Fig. 2 represents a vertical cross-section 'of the same in the directionof the line X X, exposing the forward part with the coil for thesuperheated steam. Fig. 3 represents a vertical longitudinal sectionthrough the center of boiler and furnace. Fig. 4 represents a diagram ofthe bridge-wall of my improved furnace. Fig. 5-

represents a perspective View of the coil for the superheated steam.Fig. v6 represents an end view of my furnace.

A represents a boiler with horizontal tubes, by way of illustration. .13represents my improved furnace. O O 0 represent fines for conveying airbeneath a sloping false bottom, F, and also beneath the grates K. D D Drepresent pipes for conveying air into the combustion-chamber. Erepresents the combustion-chamber for consuming smoke and gases whichpass over the bridge-wall. F represents a sloping false bottom. Grepresents a sloping bridge-wall.

side of the furnace or fire-box. I represents a coil for superheatingsteam and directing it through a row of small holes into the flames. Jrepresents a valve for regulating the amount of steam allowed to thecoil I. K represents the firegrates.

My improved furnace has the advantage of giving admission to draft onall sides, and as every one of the flues G G O is provided with a doorthe draft may safely be regulated, with regard to quantity or force, byopening a certain number of the doors mentioned and keeping the restshut. Thus an ample supply of cold air may pass through the grate- Hrepresents a pipe conducting steam to the superheating coil inbars,keeping them cool, and thereby protecting them against warping andburning at the top, at the same time presenting more nourishment to thefire, which requires less fuel for the same efi'ect. Whatever smoke andunconsumed gases are carried over the bridgewall G enter thecombustion-chamber E, the larger area of which retards their speed andaffords a good opportunity to the fresh air collected by the flues c c0, and conducted in the direction indicated by arrows, through the pipesD D D,into said combustion-chamber to mingle with them and complete theprocess of their combustion. A part of the generated steam ,is conductedthrough a pipe, H, into a coil, L'where it is superheated or separatedinto its two constituent gasesoxygen and hydrogen-(both favoringcombustion and both powerful generators of heat,) which are forced, inminute streams, through the holes 1' i i, into the flames.

The results of these improvements are, first, a never-failing supply ofdraft and heat; secondly, an uninterrupted sheet of flame under theboiler and in its tubes; thirdly, entire absence of soot along thefire-courses and in the chimney.

I claim as my invention- 1. The combination of the supply-pipe H andvalve J With the superheating-coil I, having openings 6 'i i, whenarranged in the furnace or fire-box substantially as shown, and for thepurposes herein set forth.

2. The combination of the air'pipes D D D in the bottom and sides of thefurnace, when arranged substantially as and for the purpose set forth.

3. The combination, in a boiler-furnace, of the coil I, slopingbridge-wall Gr, sloping false bottom F, flues c c c, and pipes D D D,substantially as and for the purposes hereinbefore described.

4. The combination of the main flue G with the branch fiues c c 0,arranged substantially as shown, and for the purpose set forth.

CHAS. D. SMITH. Witnesses:

JAMES S. GRINNELL,

THos. JEWELL.

